Vapor recovery system and components therefor

ABSTRACT

A system for transferring gasoline from a tank truck to an underground storage tank provides recovery of vapor displaced from the underground tank by gasoline from the tank truck. The system includes a fill tube that is coaxially mounted inside and spaced from a riser tube extending from the underground tank to a manhole to provide an annular space between the tubes from the manhole to the underground tank. The fill tube extends downwardly in the storage tank to a bottom portion of that tank for submerged filling of the tank. The system further includes a novel fitting of two pipes with a unitary construction. At the bottom end portion of the fitting the two pipes are coaxial, rectilinear and spaced from each other to provide an annular space to communicate with the annular space between the riser tube and the fill tube. At that end portion of the fitting, the outer pipe is constructed to be mounted on a male adapter permanently mounted on the top end of the riser tube. The fitting is thus mounted for a gasoline transfer operation. That end portion of the inner pipe of the fitting is constructed to be received by the top end portion of the fill tube, when the fitting is placed on the adapter. The intermediate portion of one pipe of the fitting is curved or arcuate while the intermediate portion of the other pipe is straight. The intermediate portion of one pipe extends through a wall opening in the other pipe so that the other end portions of the two pipes of the fitting are spaced apart from each other. These two pipes of the fitting at that other end are constructed to be connected to two hoses. One hose, which is a gasoline fill hose, is connected at one end to the bottom of the tank on a tank truck while the other end of the fill hose is connected to the top end of the pipe of the fitting that is inside the other pipe at the bottom end portion of the fitting. The other hose, which is a vapor recovery hose, is connected at one end to a pipe on the truck that communicates selectively with the top portion of one of the tank compartments on the truck, while the other end is connected to the pipe of the fitting that is outside the other pipe at the bottom end portion of the fitting.

United States Patent [191 Ginsburgh et al.

[451 Apr. 30, 1974 VAPOR RECOVERY SYSTEM AND COMPONENTS THEREFOR [75] Inventors: Irwin Ginsburgh, Morton Grove;

James B. Cotter, Park Forest, both of I11.

[73] Assignee: Standard Oil Company, Chicago, Ill. [22] Filed: Jan. 29, 1973 [21] Appl. No.: 327,597

[52] US. Cl 141/285, 141/346, 141/374, 285/131 [51] Int. Cl B651) 3/06 [58] Field 01 Search 141/59, 285, 295, 298, 141/299, 346, 374, 392; 285/131 56] References Cited UNITED STATES PATENTS 2,221,435 11/1940 Preston et a1 141/295 Primary ExaminerHouston S. Bell, Jr. Attorney, Agent, or Firm-Arthur G. Gilkes; William T. McClain; Claron N. White [57] ABSTRACT A system for transferring gasoline from a tank truck to an underground storage tank provides recovery of vapor displaced from the underground tank by gasoline from the tank truck. The system includes a fill tube that is coaxially mounted inside and spaced from a riser tube extending from the underground tank to a manhole to provide an annular space between the tubes from the manhole to the underground tank. The fill tube extends downwardly in the storage tank to a bottom portion of that tank for submerged filling of the tank. The system further includes a novel fitting of two pipes with a unitary construction. At the bottom end portion of the fitting the two pipes are coaxial, rectilinear and spaced from each other to provide an annular space to communicate with the annular space between the riser tube and the fill tube. At that end portion of the fitting, the outer pipe is constructed to be mounted on a male adapter permanently mounted on the top end of the riser tube. The fitting is thus mounted for a gasoline transfer operation. That end portion of the inner pipe of the fitting is constructed to be received by the top end portion of the fill tube, when the fitting is placed on the adapter. The intermediate portion of one pipe of the fitting is curved or arcuate while the intermediate portion of the other pipe is straight. The intermediate portion of one pipe extends through a wall opening in the other pipe so that the other end portions of the two pipes of the fitting are spaced apart from each other. These two pipes of the fitting at that other end are constructed to be connected to two hoses. One hose, which is a gasoline fill hose, is connected at one end to the bottom of the tank on a tank truck while the other end of the fill hose is connected to the top end of the pipe of the fitting that is inside the other pipe at the bottom end portion of the fitting. The other hose, which is a vapor recovery hose, is connected at one end to a pipe on the truck that communicates selectively with the top portion of one of the tank compartments on the truck, while the other end is connected to the pipe of the fitting that is outside the other pipe at the bottom end portion of the fitting.

16 Claims, 5 Drawing Figures VAPOR RECOVERY SYSTEM AND COMPONENTS THEREFOR BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a system for transferring gasoline from a tank truck to an underground storage tank through a fill pipe that extends from a manhole to an opening in the storage tank. To provide a sumberged fill so as to minimize vapor and mist formation from the gasoline transferred to the storage tank the fill pipe extends downwardly in the underground storage tank so that its bottom open end is located in the bottom portion of the storage tank. In such prior construction, displaced vapor passes out another opening in the tank to a conventional vent pipe that extends a substantial distance underground and then extends vertically a substantial distance so that the top open end of the pipe is a safe distance above ground level. In this construction, the displaced vapor is lost to the atmosphere.

Others have proposed various modifications of the conventional system to recover displaced vapor. These proposals are described below:

The system of the present invention is a construction that is substantial modification of such conventional system and provides recovery of the displaced vapor by transferring it to the tank compartment on the tank truck from which the gasoline is being unloaded. The new construction of the system of the invention almost eliminates loss of vapor out of the conventional vent pipe during the transferring of gasoline from the tank truck to the underground storage tank.

2. Description of the Prior Art Various proposals have been made to recover vapor from the ventpipe during the transfer of gasoline from a tank truck to an underground storage tank at a service station. Conventionally, a service station has two or more underground tanks and each of these tanks may have a-vent pipe. The outlet portion of these pipes extends upwardly at a location spaced a substantial distance from the underground tank, as mentioned above.

It has been proposed to connect these vent pipes above ground to a manifold and that manifold is provided with a system of valves such that the vent pipe connected to a storage tank receiving gasoline communicates with one endof a vapor recovery hose. The other end of that hose would be connected to the upper portion of the tank compartment on the truck from which gasoline is being discharged. There are several disadvantages to this proposed system. For example, the vapor recovery ho se would be undesirably long because it must extend a long distance from the location of the manifold to the tank truck discharging gasoline to the underground storage tank while the truck is located quite close to the manhole. The truck is thus parked so that the gasoline fill hose can be relatively short so that it can be stored on a rack on the truck when the hose is not in use.

The length of the gasolinefill hose must be such that the truck operator can readily take it off the rack, connect one end to the outlet communicating selectively with the tank compartment on the truck, and connect the other end to a fill tube at the manhole for the storage tank that will receive the gasoline. The vapor recovery hose also would be a component that is transported with the truck and thus should be sufficiently short that the truck driver, without assistance from others, can lift it from a rack, connect one end to an inlet pipe communicating with the top portion of the tank compartment and connect the other end of the hose to an outlet fitting on the manifold from-which it will receive the vapor being displaced from the underground tank. However, for use at many existing service stations the length of the vapor recovery hose, that would be required, would be such that one man could not readily load and unload that hose from the truck and move its inlet end to the manifold.

Another proposed system would provide a piping system for the vent pipes from two or more of the underground storage tanks such that all vent pipes would be connected to an upstanding pipe that would extend upwardly to another manhole. That pipe would be constructed at its top end in a manner to connect to it a vapor recovery hose that would also be connected, via piping on the truck, to the top portion of the tank compartment on the truck that is having its quantity of gasoline transferred to a particular underground storage tank. To provide this system it would be necessary to excavate for installation of an additional manhole and the additional piping connected to the vent pipes. It would be necessary also to install additional components to prevent undesirable intermixing of vapors in two storage tanks. Without such additional components the filling of one underground storage tank and displacement of the vapors could result in transfer of part of that vapor to another underground storage tank through the proposed piping system. The manhole for the pipe connected to the vent pipes may be some distan ce from the manhole containing the fill pipe for a particular underground storage tank. It could require a vapor recovery hose that would be undesirably longer than the gasoline fill hose. Other undesirable aspects of this system should be apparent.

In the United States there are tens of thousands of underground storage tanks that have a construction for splash filling. In that construction a fill tube extends only from a manhole to the top portion of the tank. In the manhole the top end of that fill tube has mounted on it a male adapter for connecting that end of the fill tube by a temporarily attached elbow to a gasoline fill hose that is also connected at its other end to the tank truck outlet for the filling operation.

To convert these underground storage tanks constructed with a fill tube for splash filling to a construction providing submerged filling there are two alternatives. One is the replacement of the existing fill tube with a longer tube that would extend to the bottom portion of the tank. This would require excavation and the total cost to convert the thousands of tanks would be prohibitive. The other alternative is to place a longer tube of smaller diameter inside the existing fill tube, to

GROUND GASOLINE STORAGE TANKS, published in the Nov., 1963, issue of Journal of the Air Pol Iution Control Association, (Vol. 13, No. ll) at pages 524-530, describes two systems for submerged filling of gasoline from a truck into an underground storage tank with vapor recovery.

The earlier of these two systems is illustrated in FIG. 5 of the article. Each truck requires a concentric hose and a special connector to communicate the inner conduit of the hose with the outlet connected selectively to the bottom portions of one of the gasoline tank compartments on the truck and to communicate the outer conduit, for vapor recovery, with a manifold piping communicating with upper portions of those compartments. The other end of the concentric hose is connected to a dual quick-connecting connector. Each storage tank is equipped with a dip tube concentrically mounted inside and spaced from the existing fill tube and extending to the bottom portion of the storage tank. On the existing fill tube is mounted a fitting, as a dual quick-coupling connector, to connect the other end of the concentric hose so that gasoline will flow into the dip tube from the inner conduit of the hose while discharged vapor passing upwardly between the dip tube and existing fill tube will flow into the outer conduit of the hose. The precise structure of the connector on the truck or the fitting on the fill tube is not disclosed. One obvious disadvantage is the weight of the concentric hose.

The other system described in the article also uses a fill tube mounted in and spaced from the existing .splash-fill tube and extending to the bottom portion of the storage tank. The top of the fill tube is connected by a valve and an adapter to an elbow that is connected to a compartment on the truck by a gasoline fill hose. The vapors discharged through the annulus between the two tubes pass through a vapor return hose connected to a side arm" in an interlock arrangement that includes the valve. The structure of the valve designed by Nishkian and Company" is not disclosed.

That Gosselin patent describes a system using the interlock valve to transfer discharged vapors to a vapor rcovery device in which the hydrocarbons are absorbed by activated carbon in a cannister. Apparently in the system ofthe published article the cannister is replaced by a removable adapter that is connected by an elbow to a vapor return hose that is connected through manifold piping to a vacuum spring-load relief valve port of the dome cap of the tank truck compartment from which gasoline is unloaded by the gasoline fill hose. The gasoline is loaded into the storage tank through the center of the valve of the interlock arrangement. That valve is opened only by connecting the adapter for the vapor return hose to a receiving member mounted on the side arm of the interlock arrangement. It is seen that the interlock arrangement has numerous components.

Between transfers of gasoline to the storage tank two caps are in place. One covers the open end of the receiving member. The other covers the open end of the adapter mounted on the valve that is fixedly mounted on each storage tank by a lock ring mounting the valve on a sleeve mounted on the existing splash-fill tube.

The sleeve has a hollow side arm that has its distal end portion turned upward for mounting on it the receiving member mentioned above. Within the receiving member is a cam finger that is moved by the adapter when it is inserted in the receiving member. This movement of the finger, that is keyed on a valve rod of the valve, opens that valve by overcoming the bias of a spring. The added submerged-fill tube is flanged at its top end. The flange rests on the sleeve where it is held in place by the lock ring mounting the valve on the sleeve.

Each storage tank requires a complete interlock arrangement including sleeve with side arm, receiving member with its cam finger, a lock ring, a valve with its rod connected to the finger, an adapter mounted on the valve and two caps. The adapter for the elbow for the vapor recovery hose is removably mounted on the receiving member because it must be removed after a gasoline transfer operation so that the spring will close the valve. After removal of that adapter a cap is placed on the receiving member.

Other less relevant patents of Charles J. Gosselin relating to vapor recovery are U.S. Pat. Nos. 2,853,149 and 2,908,299.

US. Pat. No. 2,439,887 discloses an apparatus for transferring a volatile liquid, such as gasoline, from a storage tank to a tank truck. In that apparatus, there is a nozzle that is lowered to place the nozzle in a top opening of a tank on the tank truck. Within the nozzle is located a fume tube. The construction of the nozzle is such that the conduit for the gasoline and the conduit for the fumes are in a side-by-side relationship. The fume tube has openings at different elevations to permit passage of vapor from the compartment on the tank truck, that is being loaded with gasoline, to pass into the fume tube. In this apparatus, the fume tube is in communicator, through a valved chamber, with a pipe that is connected through a hose to the upper part of the storage tank. The fume tube does not communicate with the chamber and thereby with the storage tank until the pressure in the fume tube has increased to a sufficient extent to open the valve. This apparatus would obviously be unsuitable as a replacement or modification of existing splash-fill tubes of underground storage tanks. The nozzle would provide undesirable splash filling as it would extend only to the top portion of the underground storage tank so that the fume tube could be somewhat effective. Actually the fume tube would not transfer vapor until the valve is opened. Before this would happen displaced vapor would pass out the conventional vent pipe for the underground storage tank.

SUMMARY OF THE INVENTION The system of the present invention, for transferring gasoline to underground storage tanks from a tank truck while concomitantly recovering in the tank truck vapor displaced in the storage tank receiving the gasoline, includes for each storage tank: a riser tube mounted on an underground storage tank and extending from the top of the storage tank to a manhole in the ground above the storage tank; a fill tube coaxially and mounted, preferably removably mounted, in the riser tube and extending from the bottom portion of the storage tank to an elevation above the top end of the riser tube; and an adapter fixedly mounted on the top end portion of the riser tube and extending above the top end of the fill tube, and for the tank truck includes: a gasoline fill hose having one end connectable to pipe means on the truck to communicate the hose with the bottom portion of a tank on the truck; a vapor recovery hose having one end connectable to pipe means on the truck to communicate the recovery hose with the upper portion of the tank on the truck; a fitting comprising in a unitary construction two pipes that are coaxial at their bottom ends and are spaced apart at their top ends to be connected individually to the other ends of the gasoline fill hose and theyapor recovery hose.

The fill tube has a smaller outer diameter than the inner diameter of the riser tube'to provide an annular space between them. The annular space communicates with the top portion of the chamber of the storage tank while the fill tube communicates with the bottom portion of the chamber of the storage tank. The inner diameter of the top portion of the adapter is'larger than the outer diameter of the top portion of the fill tube that is above the riser tube to provide above the riser tube a continuation of the annular space. The bottom portion of the adapter has a larger inner diameter so as to mount it on the top end portion of the riser tube.

At its bottom portion the fitting has its two pipes coaxial, rectilinear and spaced from each other. The outer pipe has its bottom end with a diameter to slide over the adapter and constructed with locking means engageable with the adapter to securely mount the fitting on the adapter for a gasoline transfer operation.

The bottom end portion of the inner pipe of the fitting and the top end part of the fill tube are constructed so that the inner pipe slidably fits into the fill tube when the fitting is slidably mounted onto the adapter.

The intermediate portion of one of the pipes of the fitting is curved while the intermediate portion of the other pipe is straight so that the one pipe extends through the wall of the other pipe. The pipe having the straight intermediate portion is preferably curved for an adjacent part of its top end portion so that its top end is above the top end portion of the other pipe so that their axes at the top ends are generally parallel. The outermost parts of top end portions of both pipes of the fittingare constructed to be connected readily to the two hoses. The vapor recovery hose is connected to the pipe that has its bottom end portion outside the bottom end portion of the other pipe that is connected at its top end to the gasoline fill hose. These hose connec tions are made after the fitting is securely mounted on the adapter. Of course, to mount the fitting on the adapter a cap is removed from the adapter. The cap, when'in place, covers the open top ends of the fill tube and the riser tube.

To ensure the coaxial location of the bottom end portion of the inner pipe of the fitting relative to the outer pipe so that the inner pipe will slide inside the fill tube,

the fitting includes spider spacer elements secured to both pipes at spaced peripheral positions in a transverse plane above but adjacent to the bottom end of the outer pipe that engages the adapter.

To ensure coaxial positioning of the fill tube relative to the riser tube the fill tube is constructed with two sets of spacer elements that are fixedly mounted on the outer surface of the fill tube at two widely spaced transverse planes. At each plane the set of spacer elements are located about the periphery in spaced relationship and are of narrow width to minimize interference with vapor flow upwardly through the annular space between the tubes. One set of the spacer elements of the fill tube is mounted on an intermediate portion of the fill tube at a transverse plane adjacent to the bottom end of the riser tube when the fill tube is mounted in position in the riser tube. The other set is mounted adjacent the top end of the fill tube andat a location to be partly above the top end of the riser tube and partly in contact with the riser tube. Each of the spacer elements of the latter set has a flange extending radially outward to rest on and be supported by the riser tube when the fill tube is in place in the riser tube. The adapter with its larger inner diameter bottom end portion has a shoulder at itsjunction with its top portion of smaller diameter. The shoulder engages the flanges of the spacer elements of that set and thereby secures the fill tube against longitudinal movement when the adapter is mounted on the riser tube after the fill tube is placed in position. This construction ensuresaxial stability of the filltube when the inner pipe at the bottom end of fitting is slid into it when mounting the other pipe of the fitting on the adapter or when removing the fitting from the adapter.

On the bottom end of the fill tube there may be mounted'means to space that tube from the bottom of the storage tank and to prevent downward axial movement of the fill tube when it is being engaged at its top portion by the inner pipe at the bottom end of the fitting. This spacing means may be absent when the upper set of spacer elements of the fill tube have the flanges mentioned above.

The fill tube adjacent the bottom end portion is preferably flared outward to provide a bottom end portion with a larger diameter to reduce pipe friction and improve flow rate of gasoline through the fill pipe.

The adapter and the riser tube of the system of the invention, and, of course, the cap used to cover the adapter between gasoline unloadings, .are components V of an existing splash fill system. Only one additional component to convert each existing tank is required to the system of the present invention. That component is the filltube'that can be installed economically and in asimple manner without any excavation and in the preferred'embodiment of construction of the system can be removed easily whenever access is desired through the existing splash-filltube, herein referred to as a riser tube of the system of the invention. The fill tube of the invention converts existing splash-fill systems to a sumberged-fill system without excavation and provides a structure at the top of the two tubes within the adapter that cooperates with the novel fitting of the invention and an extra hose, as a vapor recovery hose, to provide recovery of vapor discharged from the storage tank when adding gasoline to the tank.

Only one fitting and one vapor recovery hose, along with the conventional gasoline fill hose, are required for each gasoline tank truck that can unload gasoline into tanks at many service stations. The fitting and the hoses can be readily connected to existing storage tanks when each is modified with the novel fill tube of the invention.

DESCRIPTION OF THE. DRAWINGS FIG. 1 is a fragmentary vertical section of a preferred embodiment of the system of the invention showing the fitting of the invention mounted on the male adapter that is mounted on the riser tube, but does not show the gasoline fill hose and the vapor recovery hose of the system.

FIG. 2 is a view like FIG. I but showing the fitting separated from the adapter mounted on the riser tube and separated from the fill tube.

FIG. 3 is a cross section taken along line 3-3 of FIG. 1.

FIG. 4 is a cross section taken along line 4-4 of FIG. 2.

FIG. is a schematic view of the system of the invention and showing in addition the connection of the two hoses to a tank truck and showing in dotted lines an alternative connection of the vapor recovery hose to the tank truck.

DETAILED DESCRIPTION Referring to FIG. 1, an underground storage tank 11 has a top opening 12. A flanged pipe fitting 13 is fixedly mounted on tank 11 at oening 12. A riser tube 15 is fixedly mounted by pipe fitting 13 so that tube is coaxial with opening 12. The riser tube 15 extends upwardly from tank 11 to a manhole 16 in ground G (FIG. 5). This is a conventional construction for existing splashfill tubes mounted on underground storage tanks. In that conventional construction, as in the case of the construction of the system of the present invention, a male adapter 17 is mounted on tube 15. The main top portion of the central cylindrical hole of male adapter 17 has the same inner diameter as of tube 15. The bottom portion has a large inner diameter and is internally threaded to be screwed onto the externally threaded top end portion of tube 15. The male adapter 17 is constructed at its top portion with an annular groove on its outer surface to receive locking fingers of cams, such as cams 18, that are pivotly mounted on a skirt of a cap (not shown) that is in place except when there is a transfer of gasoline from a tank truck to storage tank 11. In the conventional system that cap is removed, an elbow with such locking cams on its bottom end portion is mounted and locked on adapter 17 and a gasoline fill hose is connected to the other end of the elbow. The other end of that hose is connected to a pipe outlet of the tank truck that communicates through a valve with the bottom portion of a tank compartment on the truck.

In the system of the present invention, a fill tube 19 is present within riser tube 15. The fill tube 19 extends downwardly in tank 11 to a depth such that its bottom open end is in the bottom portion of the tank 11 for a submerged filling operation, as seen in FIGS. 1 and 2. The outer diameter of tube 19 is smaller than the inner diameter of tube 15 so that there is an annular space between these tubes. The tubes 15 and 19 are maintained in a coaxial relationship by a set of narrow spider spacer elements 20, fixedly mounted on an intermediate portion of tube 19 at a transverse plane adjacent the bottom end of tube 15. The spacer elements 20 are located about the periphery of tube 19. The elements 20 contact tube 15 to maintain an annular space between the tubes at this elevation. There are also mounted on tube 19 at the higher location a number of narrow spider spacer elements 21, that are similarly fixedly mounted on tube 19 adjacent the top end of tube 15. The elements 21 also contact tube 15 to cooperate with elements 20 in maintaining a coaxial spaced relationship of these tubes from one end of tube 15 to its other end.

The upper portion of each element 21 has a flange 22, that extends radially outward with respect to the axis of tube 19. The elements 21, are located on tube 19, so that flanges 22 rest on the top end of tube 15. The flanges 22 of spacer elements 21 limit the extent to which tube 19 when it is inserted in tube 15 can be lowered into tank 11. When flange 22 rests on tube 15, the bottom open end of tube 19 is spaced above the bottom of tank 11 and the top open end of tube 19 is at an elevation above that of tube 15. After insertion of tube 19 into tube 15, adapter 17 is mounted on the top end of tube 15 and secured to it by engaging the externally threaded top end portion of tube 15 until the internal shoulder of adapter 17 contacts flange 22 and secures them against the top end of tube 15.

In the preferred construction, as shown, tube 19 is flared outwardly adjacent its bottom end portion and the bottom end portion of tube 19 has a larger diameter than the upper part of tube 19. In addition, the end of tube 19 is oblique or beveled to provide flow of gasoline from tube 19 into tank 11 with minimum turbulence so as to minimize formation of vapor.

The system of the invention includes a fitting with a unitary construction and generally indicated at 23. The fitting 23 comprises a pipe 24 and a pipe 25. At the bottom end portion of fitting 23, pipe 25 is inside, coaxial with and spaced from pipe 24 to provide an annular space in alignment with the annular space between tubes 15 and 19 when fitting 23 is mounted on adapter 17. Adjacent the bottom end portion of pipe 25, it is inwardly flared slightly so that the end portion has a slightly smaller diameter than the intermediate portion of pipe 25. The outer diameter of that end portion of pipe 25 is such, in any event, that it is slidably received in the top end portion of tube 19. The tube 19 is slightly flared outwardly at its extreme end to facilitate entry of the end portion of pipe 25 when mounting fitting 23 onto male adapter 17.

The coaxial relationship between these two bottom end portions of pipes 24 and 25 is ensured by the presence of narrow spider spacer elements 26 secured to pipe 25 and to pipe 26 adjacent the bottom end of fitting 23 and located about the periphery of pipe 25 at a transverse plane above the flared portion of pipe 25 mentioned above. Below spacer elements 26, the bottom end portion of pipe 24 is offset radially outward to provide an internal shoulder. Below that shoulder pipe 24 has a larger inner diameter due to the offset so that pipe 24 can be mounted onto male adapter 17. That lowermost end portion of pipe 24 has a pair of cams 18 pivotally mounted on it. The cams 18 are moved from the position in FIG. 2 to the position in FIG. 1 to lock fitting 23 on adapter 17.

As is seen in FIGS. 1 and 3, each cam 18 is pivotally mounted on a shaft 27 supported by a pairof spaced lugs 28 integral with pipe 24 and on opposite sides of a slot in pipe 25 through which the locking finger of cam 18 extends when the other end of cam 18 is moved downwardly. At the locking position the finger engages the annular groove 29 in male adapter 17. This lockingcam construction of the bottom end portion of pipe 24 is like the locking-cam construction of cover cap for the closing of a conventional splash-fill tube of existing underground storage tanks and like the locking-cam construction of the bottom end portion of an elbow conventionally mounted on an adapter to connect a gasoline fill hose to the tank.

The inner surface of pipe 24 below but next to the radially outward offset has an annular groove in which is mounted the peripheral margin of a gasket 30 that is contacted by the top surface of adapter 17 and backed up by the internal shoulder of pipe 24 provided by the offset. The gasket 30 provides a seal to reduce loss of vapor between fitting 23 and adapter 17. Because the weight of the ends of the two hoses, when connected to the top ends of pipes 24 and 25 of fitting 23, can affect the suitability of the seal by gasket 30, the adapter 17 of the present invention preferably includes an O-ring 30 mounted in an annular groove in the outer. surface of adapter 17, below the groove engaged by locking cams l8, and engaging the inner surface of the bottom end portion of tube 24 below its slots that contain earns 18.

The intermediate portion of pipe 24 is curved, whereas the intermediate portion of pipe 25 is straight and thus passes through the outermost wall part of the curved intermediate portion of pipe 24 where the two pipes are welded together to provide another part of the unitary construction. The top end portion of pipe 24 is straight. The part of the top end portion of pipe 25 that is adjacent its straight intermediate portion is curved in the same plane and direction as the curved intermediate portion of pipe 24 so that the top ends of the pipes are in a side-by-side relationship.

In the specific construction of fitting 23, that is shown in FIG. 1, the top end portion of pipe 24 includes at its outermost part a reducer pipe section 31, that is flanged at its distal end, and a flanged male adapter 32 that is bolted to flanged pipe section 31. A vapor recovery hose 34 is connected to adapter 31 when gasoline is to be transferred to tank 11.

The comparable end portion of pipe 25 is straight except for the curved partadjacent the straight intermediate portion mentioned above. The diameter of that straight part of the top end portion of pipe 25 is increased to the top end by the inclusion of an inverted reducer pipe section 35 that is flanged at its distal end. A male adapter that is similarly flanged is bolted to flanged pipe section 35. The increase in the diameter to that end of pipe 25 is provided to correspond to a conventional diameter of adapter 36 that is a diameter required to connect to one end of gasoline fill hose 37 r of conventional size. In an existing system that end of gasoline hose 37 is connected by an elbow to an adapter 17 mounted on tube 15. The inner diameter of adapter 36 corresponds to the inner diameter of adapter 17.

In the case of the top end of pipe 24', its inner diameter to its top end is reduced by reducer section 31 to connect to male adapter 32 that has a size to connect to a suitable hose 34 for recovery of the gasoline vapor discharged from tank 11-. In the preferred embodiment the inner diameters of adapter 32 and hose 34 are such that the areas correspond generally to the area of the annular space between pipes 24 and 25 at the bottom end portion of fitting 23 where they are coaxial and thus the area of the'annular space between tubes and 19.

A U-shaped support strap 38, with its web contacting the bottom of tank 11, is mounted on the bottom end of tube 19. The support strap 38 is present, when flanges 22 are not present on spider spacer elements 21, to ensure the mounting of tube 19 so that its bottom end is spaced from the bottom wall of tank 11 and to prevent downward movement of tube 19 when pipe 25 is slid into it during mounting of fitting 23 on adapter 17.

The fitting 23 has a brace 39 welded at'its ends to the top end portions of pipes 24 and 25 to prevent relative movement of the pipes. Such movement would be undesirable. It could change the relative positions of the bottom ends of pipes 24 and 25 so that pipe 25 would not engage tube 19 adequately, if at all, whenfitting 23 is mounted on adapter 17. The fitting 23 has a handle 40 mounted on the top surface of the curved part of the top portion of pipe 25 for easier portability of fitting 23 and ease of maneuvering fitting 23 onto adapter 17.

Referring to FIG. 5, tank 11 has, as in a conventional construction, a vent pipe 41 that communicates with a top opening in tank 11 and extends a substantial distance underground from tank 1 1 to a place where it extends vertically to a substantial elevation above ground. Illustratively, as in a conventional system, a gasoline withdrawal pipe 42 extends upwardly from the bottom portion of tank 11 and through the top wall of tank 11 to a check valve 43 through which it communicates with a pipe 44 that extends to a suction pump (not shown) at a service station island to provide gasoline through a hose and nozzle to an automobile gasoline tank. I

In FIG. 5, adapter 36 is connected by hose 37 to a conventional bottom outlet of a tank truck generally indicated at 46. That outlet is in a piping system that communicates selectively with the different tank compartments of a tank truck 46. The vapor recovery hose 34, that is connected one end to adapter 32, is' connected to a pipe 47 that is connected to a manifold pipe 48. The manifold pipe 48 is connected to each tank compartment by a pipe 49 that is connected to a valve at the top of that compartment. That valve is opened when the valve at the bottom of that tank compartment is opened to discharge gasoline by hose 37 into tank 11.

Although the top end of vent pipe 49 may have a conventional weather cap 50 mounted on it to prevent ingress of rain without impairment of outflow of vapor or ingress of air when breathing of tank 11 is required between transfers of gasoline into tank 11, and although the inner diameter of vent pipe 41 may be of a conventional size, it is preferred that pipe 41, in a new installation of storage tank and the system of the invention, have a substantially smaller diameter to reduce vapor loss out pipe 41 when loading tank 11. This is possible because, in the system of the present invention, vent pipe 41 is not required to remove displaced vapor but is required only for the breathing of tank 11 after a loading until the next loading. To modify an existing storage tank system with its installed vent pipe, on top of the vent pipe there is preferably installed means to substantially restrict the flow of vapor out the existing pipe. As suggested in the article mentioned above, for the systems described there, a pressurevacuum valve could be installed on the top end of vent pipe 41 in the system of the present invention.

In view of the foregoing description of the preferred embodiment of fitting 23 of the invention it should be apparent that in an alternative embodiment of the fitting the vapor recovery pipe, i.e., pipe24, would have a straight intermediate portion and the intermediate portion 'of the gasoline fill pipe, i.e., pipe 25, would be curved. In that case the curved intermediate portion of pipe 25 would extend through the straight wall of the intermediate portion of pipe 24. Thus in the fitting of the invention, one of the pipes of the fitting is straight and the other is curved at their intermediate portions so that the pipes are coaxial at their bottom end portions and are spaced apart at their top end portions. Preferably the top end portions are in a side-by-side relationship by having a curved construction for the pipe having a straight intermediate portion at an elevation above but adjacent the straight intermediate portion.

For a new installation of storage tank and the system of the present invention, it would not be necessary to use pipe section 35. Instead pipe 25 would be longer and flanged at its end or externally threaded and adapter 36 would be mounted on that end. In that case, pipe 25 would have the same inner diameter as the outer end portion of male adapter 36. The diameters of tubes 15 and 19 would be increased and, of course, the diameters of pipe 24 and adapter 17 would be increased. This would be possible for a new installation but would not be economically feasible for a modification of existing underground storage tanks because such modification would require excavation to replace the existing splash-fill tubes with riser tubes 15 oflarger diameter.

The foregoing description has been presented as examples of the system of the invention and of components of the invention used in that system. Theinvention is limited solely by the claims that follow:

We claim:

1. A system for transferring gasoline from a tank truck to an underground storage tank and concomitantly recovering vapor, displaced from the storage tank by the entering gasoline, by transferring the vapor to the tank truck, said storage tank having a riser tube mounted on the storage tank at a top opening to communicate with the top portion of the storage tank and extending to a manhole in the ground, which comprises for the storage tank:

a gasoline fill tube mounted inside said riser tube with an annular space between the riser tube and the fill tube, said fill tube extending from the bottom portion of the storage tank to an elevation above the top end of the riser tube; and and an adapter fixedly mounted on the top end portion of the riser tube and extending above it and above the top end of the fill tube, said adapter having a cylindrical central opening that is coaxial with the riser tube and that has generally the same diameter as the inner diameter of the riser tube to provide an annular space between the adapter and the fill tube in alignment with the annular space between the riser and fill tubes, and

which comprises for transport with the tank truck:

a fitting removably mountable on said adapter and containing in a unitary construction: a first pipe having:

a top end portion constructed to be connectable with a gasoline fill hose to communicate said first pipe with a tank truck outlet for gasoline from a tank on the truck; and

a bottom end portion construction to fit into the top end portion of said fill tube when said fitting is mounted on said adapter; and

a second pipe having:

a top end portion spaced apart from the top end portion of said first pipe and constructed to be connectable with a vapor hose to communicate said second pipe with a piping system on the truck communicating with the top portion of the tank on the truck; and

a bottom end portion that is coaxial with, outside and extending below the bottom end portion of said first pipe and that is constructed to mount said fitting on said adapter,

one of said first and second pipes having a rectilinear intermediate portion and the other of said pipes having a curved intermediate portion so that one of said intermediate portions extends through a wall opening in the other intermediate portion and said pipes being fixedly secured to each other at this junction of said intermediate portions of said pipes.

2. The system of claim 1 wherein said first pipe of said fitting has said rectilinear intermediate portion and said second pipe of said fitting has said curved intermediate portion so that said first pipe extends upwardly through an opening in a wall part of said intermediate portion of said second pipe.

3. The system of claim 2 wherein the part of said top end portion of said first pipe that is adjacent said intermediate portion of said first pipe is curved in the same vertical plane and generally in the same direction as said intermediate portion of said second pipe and wherein said top end portions of said first and second pipes are connected to each other by brace means to prevent relative vertical movement of said pipes that would change the relative elevations of the bottom ends of said first and second pipes.

4. The system of claim 1 wherein:

said bottom end portion of said second pipe is offset radially outward adjacent but spaced from its bottom end to provide below the offset a part of said second pipe that has a larger inner diameter for mounting said fitting on said adapter;

said part of said second pipe having a larger inner diameter has vertical slots in it;

said fitting has locking cams pivotally mounted on said part of said second pipe that has said larger inner diameter for locking movement through said slots of said second pipe;

said adapter has an annular groove in its outer surface engageable by said cams when said fitting is mounted on said adapter; and

said fitting includes spacer elements secured to the bottom end portions of said first and second pipes at spaced locations about the annulus between these pipes at an elevation above said offset of said second pipe.

5. The system of claim 1 wherein said fill tube includes as an integral part of its construction first and second sets of spacer elements rigidly mounted on the outer surface of said fill tube, with the spacer elements of each set being spaced from one another about the periphery of said fill tube, the first set of spacer elements being located at an intermediate portion of said fill tube and the second of spacer elements sets being located adjacent but spaced from the top end of said fill tube so that the first set contacts the bottom end portion of said riser tube and the second set contacts the top end portion of said riser tube when said fill tube is mounted in said riser tube.

6. The system of claim 5 wherein said second set of spacer elements of said fill tube have radially outward flanges for a top portion of each to be supported on the top end of said riser tube and to be held between said adapter and the top end of said riser tube.

7. The system of claim 6 wherein said first pipe of said fitting has said rectilinear intermediate portion and said second pipe of said fitting has said curved intermediate portion so that said first pipe extends upwardly through an opening in a wall part of said intermediate portion of said second pipe.

8. The system of claim 7 wherein: the part of said top end portion of said first pipe that is adjacent said intermediate portion of said first pipe is curved in the same vertical plane and generally in the same direction as said intermediate portion of said second pipe; said top end portions of said first and second pipes are connected to each other by'brace means to prevent relative vertical movement of said pipes that would change the relative elevations of the bottom ends of said first and second pipes; said bottom end portion of said second pipe is offset radially outward adjacent but spaced from its bottom end to provide below the offset a part of said second pipe that has a larger inner diameter for mounting said fitting on said adapter; said part of said second pipe having a larger inner diameter has vertical slots in it;

said fitting has locking cams pivotally mounted on said part of said second pipe that has said larger inner diameter for locking movement through said slots of said second pipe; I

said adapter has an annular groove in its outer surface engageable by said cams when said fittingis mounted on said adapter; and

said fitting includes spacer elements secured to the bottom end portions of said first and second pipes at spaced locations about the annulus between these pipes at an elevation above said offset of said second pipe.

9. A gasoline fill tube for an underground storage tank having a tank opening and a riser tube mounted on said tank at said opening, which comprises in a unitary construction a gasoline fill pipeconstructed for mounting inside of said riser tube to extend from a bottom portion of said tank'to an elevation above the top of said riser tube, and first and second sets of spacer elements rigidly mounted on the outer surface of said gasoline fill pipe with the spacer elements of each set tube for outward flow of vapor from said tank and to.

maintain acoaxial relationship between said riser tube and said gasoline fill pipe, said first set of spacer elements being located at an intermediate portion of said gasoline fill pipe to contactthe bottom portion of said riser tube sand said second set of spacer elements being located adjacent but spaced from the top end of said gasoline fill pipe 'to contact the top end portion of said riser tube.

10. The gasoline fill tube of claim 9 wherein said second set of spacer elements of said fill tube have radially outward flanges for a portion of each closest to said one end of said tube to rest on said riser tube when the fill tube extends fromthe bottom portion of the storage tank.

11. The gasoline fill tube of claim 9 wherein said fill tube has its said one end bevelled and its other end is slightly flared outwardly.

12. A fitting'constructed to be removably mountable on a male adapter mounted on the upper end of a riser tube of an underground storage tank'and surrounding the upper end portion of a fill tube mounted inside of, annularly spaced from and extending above and below r 14 the riser tube mounted on the underground storage tank, said fitting containing in a unitary construction:

a first pipe having:

. a top end portion constructed for connection with a gaoline fill hose to communicate said first pipe with a tank truck outlet for gasoline from a tank on the truck; and

a bottom end portion constructed for fitting into the top end portion of said fill tube when said fitting is mounted on said male adapter; and

a second pipe having:

a top end portion spaced apart from the top end portion of said first pipe and constructed for connection with a vapor hose to communicate said second pipe with a piping system on the truck communicating with the top portion of the tank on the truck; and

a bottom end portion that is coaxial with, outside and extending below the bottom end portion of said first pipe and that is constructed as a femae adapter to mount said firting on said male adapter on said riser tube and to locate said bottom endportion of said second pipe in engagement with said male, adapter,

one of said first and second pipes having a rectilinear intermediate portion and the other of said pipes having a curved intermediate portion so that one of said intermediate portions extending through a wall opening in the other intermediate portion and said pipes being fixedly secured to each other at this junction of said intermediate portions of said pipes.

13. The fitting of claim 12 wherein said first pipe of said fitting has said rectilinear intermediate portion and said second pipe of'said fitting has said curved interme- -diate portion so that said first pipe extend upwardly through an opening in a wall part of said intermediate portion of said second pipe.

14. The fitting of claim 13 wherein the part of said top end portion of said first pipe that is adjacent said intermediate portion of said first pipe is curved in the prevent relative vertical movement of said pipes that would change the relative elevations of the bottom ends of said first and second pipes.

15; The fitting of claim 12 wherein: I said bottom end portion of said second pipe to provide the construction as a female adapter is offset radially outward adjacent but spaced from its bottom end to. provide below the offset a part of said second pipe that has a larger inner diameter for mounting said fitting on said male adapter; said part of said second pipe having a larger inner diameter has vertical-slots in it; said fitting has locking cams pivotally mounted on said part of .saidsecond pipe that has said larger inner diameter for locking movement through said slots of said second pipe by engagement with an annular groove in the outer surface of the male adaptor to provide said locking engagement with said male adapter; and said fitting includes spacer elements secured to the bottom end portions of said firstv and second pipes at spaced locations about the annulus between said second pipe of said fitting has said curved intermethese pipes at an elevation above said offset of said diate portion so that said first pipe extends upwardly second pipe. through an opening in a wall portion of said intermedi- 16. The fitting of claim 15 wherein said first pipe of ate portion of said second pipe. said fitting has said rectilinear intermediate portion and 5 UQNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTIGN Patent No.3 ,807 ,465 Dated April 30 1974 Inventofl Irwin Ginsburgh et a1.

It is certified that error appears in the above-identified patent and that said' Letters Patent are hereby corrected as shown below:

Column 1, line 10, "sumberged" should read submerged- Column .2, line 61, "to the truck" should read on the truck-- Column 3, line 37 "That Gosselin patent" should read Gosselin U.S. Pat. No. 2 2 Column 6, line 31, "to convert each existing tank'is required" should read is required to convert each existing tank--'. Column 7, line 10, "oening" should read opening-. Column 11, line 36, "and and" should read and--.

. Line 54 "construction" should read --constructed-- Column 13, line 50, "sand" should read and. Column 14, line 6, "gaoline" should read --gasoline-.

Line 21, "femae" should read --fema1e-. Line 22, "firting" should read -fitting--. Line 29, "extending" should read --extends-. Column 16, line 3, "portion" should read --part--.

Signed and sealed this 24th day of September 1974.

(SEAL) Attest:

McCOYM. GIBSON JR. c. MARSHALL DANN Attesting Officer Commissioner of Patents 

1. A system for transferring gasoline from a tank truck to an underground storage tank and concomitantly recovering vapor, displaced from the storage tank by the entering gasoline, by transferring the vapor to the tank truck, said storage tank having a riser tube mounted on the storage tank at a top opening to communicate with the top portion of the storage tank and extending to a manhole in the ground, which comprises for the storage tank: a gasoline fill tube mounted inside said riser tube with an annular space between the riser tube and the fill tube, said fill tube extending from the bottom portion of the storage tank to an elevation above the top end of the riser tube; and and an adapter fixedly mounted on the top end portion of the riser tube and extending above it and above the top end of the fill tube, said adapter having a cylindrical central opening that is coaxial with the riser tube and that has generally the same diameter as the inner diameter of the riser tube to provide an annular space between the adapter and the fill tube in alignment with the annular space between the riser and fill tubes, and which comprises for transport with the tank truck: a fitting removably mountable on said adapter and containing in a unitary construction: a first pipe having: a top end portion constructed to be connectable with a gasoline fill hose to communicate said first pipe with a tank truck outlet for gasoline from a tank on the truck; and a bottom end portion Construction to fit into the top end portion of said fill tube when said fitting is mounted on said adapter; and a second pipe having: a top end portion spaced apart from the top end portion of said first pipe and constructed to be connectable with a vapor hose to communicate said second pipe with a piping system on the truck communicating with the top portion of the tank on the truck; and a bottom end portion that is coaxial with, outside and extending below the bottom end portion of said first pipe and that is constructed to mount said fitting on said adapter, one of said first and second pipes having a rectilinear intermediate portion and the other of said pipes having a curved intermediate portion so that one of said intermediate portions extends through a wall opening in the other intermediate portion and said pipes being fixedly secured to each other at this junction of said intermediate portions of said pipes.
 2. The system of claim 1 wherein said first pipe of said fitting has said rectilinear intermediate portion and said second pipe of said fitting has said curved intermediate portion so that said first pipe extends upwardly through an opening in a wall part of said intermediate portion of said second pipe.
 3. The system of claim 2 wherein the part of said top end portion of said first pipe that is adjacent said intermediate portion of said first pipe is curved in the same vertical plane and generally in the same direction as said intermediate portion of said second pipe and wherein said top end portions of said first and second pipes are connected to each other by brace means to prevent relative vertical movement of said pipes that would change the relative elevations of the bottom ends of said first and second pipes.
 4. The system of claim 1 wherein: said bottom end portion of said second pipe is offset radially outward adjacent but spaced from its bottom end to provide below the offset a part of said second pipe that has a larger inner diameter for mounting said fitting on said adapter; said part of said second pipe having a larger inner diameter has vertical slots in it; said fitting has locking cams pivotally mounted on said part of said second pipe that has said larger inner diameter for locking movement through said slots of said second pipe; said adapter has an annular groove in its outer surface engageable by said cams when said fitting is mounted on said adapter; and said fitting includes spacer elements secured to the bottom end portions of said first and second pipes at spaced locations about the annulus between these pipes at an elevation above said offset of said second pipe.
 5. The system of claim 1 wherein said fill tube includes as an integral part of its construction first and second sets of spacer elements rigidly mounted on the outer surface of said fill tube, with the spacer elements of each set being spaced from one another about the periphery of said fill tube, the first set of spacer elements being located at an intermediate portion of said fill tube and the second of spacer elements sets being located adjacent but spaced from the top end of said fill tube so that the first set contacts the bottom end portion of said riser tube and the second set contacts the top end portion of said riser tube when said fill tube is mounted in said riser tube.
 6. The system of claim 5 wherein said second set of spacer elements of said fill tube have radially outward flanges for a top portion of each to be supported on the top end of said riser tube and to be held between said adapter and the top end of said riser tube.
 7. The system of claim 6 wherein said first pipe of said fitting has said rectilinear intermediate portion and said second pipe of said fitting has said curved intermediate portion so that said first pipe extends upwardly through an opening in a wall part of said intermediate portion of said second pipe.
 8. The system of claim 7 wherein: the part of said top end portIon of said first pipe that is adjacent said intermediate portion of said first pipe is curved in the same vertical plane and generally in the same direction as said intermediate portion of said second pipe; said top end portions of said first and second pipes are connected to each other by brace means to prevent relative vertical movement of said pipes that would change the relative elevations of the bottom ends of said first and second pipes; said bottom end portion of said second pipe is offset radially outward adjacent but spaced from its bottom end to provide below the offset a part of said second pipe that has a larger inner diameter for mounting said fitting on said adapter; said part of said second pipe having a larger inner diameter has vertical slots in it; said fitting has locking cams pivotally mounted on said part of said second pipe that has said larger inner diameter for locking movement through said slots of said second pipe; said adapter has an annular groove in its outer surface engageable by said cams when said fitting is mounted on said adapter; and said fitting includes spacer elements secured to the bottom end portions of said first and second pipes at spaced locations about the annulus between these pipes at an elevation above said offset of said second pipe.
 9. A gasoline fill tube for an underground storage tank having a tank opening and a riser tube mounted on said tank at said opening, which comprises in a unitary construction a gasoline fill pipe constructed for mounting inside of said riser tube to extend from a bottom portion of said tank to an elevation above the top of said riser tube, and first and second sets of spacer elements rigidly mounted on the outer surface of said gasoline fill pipe with the spacer elements of each set being spaced from one another about the periphery of said gasoline fill pipe and constructed to provide an annular space between said gasoline fill pipe and said riser tube for outward flow of vapor from said tank and to maintain a coaxial relationship between said riser tube and said gasoline fill pipe, said first set of spacer elements being located at an intermediate portion of said gasoline fill pipe to contact the bottom portion of said riser tube sand said second set of spacer elements being located adjacent but spaced from the top end of said gasoline fill pipe to contact the top end portion of said riser tube.
 10. The gasoline fill tube of claim 9 wherein said second set of spacer elements of said fill tube have radially outward flanges for a portion of each closest to said one end of said tube to rest on said riser tube when the fill tube extends from the bottom portion of the storage tank.
 11. The gasoline fill tube of claim 9 wherein said fill tube has its said one end bevelled and its other end is slightly flared outwardly.
 12. A fitting constructed to be removably mountable on a male adapter mounted on the upper end of a riser tube of an underground storage tank and surrounding the upper end portion of a fill tube mounted inside of, annularly spaced from and extending above and below the riser tube mounted on the underground storage tank, said fitting containing in a unitary construction: a first pipe having: a top end portion constructed for connection with a gaoline fill hose to communicate said first pipe with a tank truck outlet for gasoline from a tank on the truck; and a bottom end portion constructed for fitting into the top end portion of said fill tube when said fitting is mounted on said male adapter; and a second pipe having: a top end portion spaced apart from the top end portion of said first pipe and constructed for connection with a vapor hose to communicate said second pipe with a piping system on the truck communicating with the top portion of the tank on the truck; and a bottom end portion that is coaxial with, outside and extending below the bottom end portion of said first pipe and that is constructed as a femae adapter to mount said firting on said male adapter on said riser tube and to locate said bottom end portion of said second pipe in engagement with said male adapter, one of said first and second pipes having a rectilinear intermediate portion and the other of said pipes having a curved intermediate portion so that one of said intermediate portions extending through a wall opening in the other intermediate portion and said pipes being fixedly secured to each other at this junction of said intermediate portions of said pipes.
 13. The fitting of claim 12 wherein said first pipe of said fitting has said rectilinear intermediate portion and said second pipe of said fitting has said curved intermediate portion so that said first pipe extend upwardly through an opening in a wall part of said intermediate portion of said second pipe.
 14. The fitting of claim 13 wherein the part of said top end portion of said first pipe that is adjacent said intermediate portion of said first pipe is curved in the same vertical plane and generally in the same direction as said intermediate portion of said second pipe and wherein said top end portions of said first and second pipes are connected to each other by brace means to prevent relative vertical movement of said pipes that would change the relative elevations of the bottom ends of said first and second pipes.
 15. The fitting of claim 12 wherein: said bottom end portion of said second pipe to provide the construction as a female adapter is offset radially outward adjacent but spaced from its bottom end to provide below the offset a part of said second pipe that has a larger inner diameter for mounting said fitting on said male adapter; said part of said second pipe having a larger inner diameter has vertical slots in it; said fitting has locking cams pivotally mounted on said part of said second pipe that has said larger inner diameter for locking movement through said slots of said second pipe by engagement with an annular groove in the outer surface of the male adaptor to provide said locking engagement with said male adapter; and said fitting includes spacer elements secured to the bottom end portions of said first and second pipes at spaced locations about the annulus between these pipes at an elevation above said offset of said second pipe.
 16. The fitting of claim 15 wherein said first pipe of said fitting has said rectilinear intermediate portion and said second pipe of said fitting has said curved intermediate portion so that said first pipe extends upwardly through an opening in a wall portion of said intermediate portion of said second pipe. 